Hydrophobic ceramic capillary membranes for versatile virus filtration

• Published in: Journal of membrane science 2019-01, Vol.570-571, p.85-92
• Main Authors: Bartels, Julia, Batista, Artur Guedert, Kroll, Stephen, Maas, Michael, Rezwan, Kurosch
• Format: Article
• Language: English
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2018.10.022

In this study, we present hydrophobic yttria-stabilized zirconia capillary membranes conditioned for virus filtration. These macroporous ceramic filters (d50 = 150 nm) efficiently extract viruses regardless of their surface charge with high throughput rates. For hydrophobic functionalization of the ceramic membranes we used two different silanes, n-hexyltriethoxysilane (HTS, C6-chain) and n-octyltriethoxysilane (OTS, C8-chain), in three different molarities. The virus retention of the membranes is tested in dead-end mode by intracapillary virus feeding using two small bacteriophages as model species: MS2 and PhiX174. Virus retention increases most strongly for hydrophobic capillaries functionalized with 0.05 M OTS, showing a virtually complete retention with log-reduction values (LRVs) of ~ 9 for both bacteriophages compared to the non-functionalized membrane with LRVs of 0.3 ± 0.1 for MS2 and 3.4 ± 0.2 for PhiX174. The functionalized membranes allow a high membrane flux of ~ 150 L/(m2hbar), with throughput rates up to ~ 400 L/(m2 h) while maintaining high filtration efficiency. Even under varying feed conditions using only mono- or divalent salt ions or pH values ranging from 3 to 9, retention capacities of the capillary membranes are high. Accordingly, such hydrophobic ceramic membranes offer a versatile alternative to conventional polymeric membranes for virus removal with greatly improved membrane flux. •Virus retention can be increased with hydrophobic ceramic membranes.•Virus retention increases the most for capillaries silanized with 0.05 M noctyltriethoxysilane.•The silane is stably bonded to the surface over a period of at least 3 weeks even under flow conditions.•The membranes allow a high membrane flux of ~150 L/(m2 h bar), with throughput rates up to ~ 400 L/(m2 h).